Sokel
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You can replace "water" with "acid" in your analogy.
It's closer to application.
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Fosi Audio V3 op-amp rolling, has anyone tried it? Snake oil? Or are there actual differences?
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It's closer to application.
Down South
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All hearing is subjective, it can't be anything else. The absolutists cannot accept this. It doesn't matter that a piece of equipment may measure 'perfectly' - 'optimum' is a better adjective to use.But this will only show a set of "measurements" and not the subjective personal hearing impressions one (the actual listener) is experiencing...
However each person will 'hear' differently. Even under 'perfect' D/B conditions no two people will hear the same or even remotely near the same. If as will happen in the near future robots will be equipped with far superior hearing software and 'listening devices' then these androids being built using the same materials/process will hear the 'same' because their construction and capability will be identical - what part of this does anyone not understand.
It is quite possible that 'absolutists' do hear the same because they have been programmed or programmed themselves to obey their programming - they are not actually listening - their programming has kicked in 'this is what you are hearing'. I don't disagree about the importance of measurements, they should always be the start point.
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Not under controlled, unsighted testing with levels matched to 0.1V.
Measured effect of op-amp rolling on a phono equalizer input-shorted noise
Op-amp rolling the stereo x LUXMAN LXV-OT10 Background Last month, I put together a Luxman "kit" phono equalizer and posted the measurements. https://www.audiosciencereview.com/forum/index.php?threads/luxman-lxv-ot10-phono-equalizer-amplifier-review-and-measurements.48055/ TLDR? The Luxman...
www.audiosciencereview.com
Op amp rolling can make a difference in high gain moving coil phono preamps. The key was that the MUSES op amp with pretty lousy published specifications actually measured very well. This might be why people often like MUSES subjectively despite average published specifications.
Lower gain amplifiers may be less dependent on the op amp’s gain.
Name one.
I think you go wrong when you make the error that is tragically common among audio fans of using "subjective" to mean "without controls." "Subjective" only means "evaluated with human senses." "Subjective" can be valid and objectively verified (basic ears only controls) or absolutely worthless (e.g., peeking, no rigorous level-matching).
I'm still wondering about the "subjective" aspects of individual and personal hearing.
Everyone can follow the course of his believing. If one doesn't hear a difference for whatever reason: its fine with me. If one does hear a difference: it is fine also.
There is no way of "proving" what You actually hear or are supposed to hear or not. Because people have to spent their money where their mouth is, that is OK with me too.
I don't have the means to judge "objectively" if something really exists or not because it is based on "personal believe" not measurement. No one really knows. if those measurements do cover really all aspects, which might be relevant for our human hearing with its individual . The "believe" is here: it does, but lastly nobody knows for sure...
Everyone can follow the course of his believing. If one doesn't hear a difference for whatever reason: its fine with me. If one does hear a difference: it is fine also.
There is no way of "proving" what You actually hear or are supposed to hear or not. Because people have to spent their money where their mouth is, that is OK with me too.
I don't have the means to judge "objectively" if something really exists or not because it is based on "personal believe" not measurement. No one really knows. if those measurements do cover really all aspects, which might be relevant for our human hearing with its individual . The "believe" is here: it does, but lastly nobody knows for sure...
Killingbeans
Major Contributor
The only way to make an "approved" circuit, is to design something that is able to tolerate wildly different op-amp specs. Correct me if I'm wrong, but doesn't leave you much else than a simple unity, or near-unity, gain buffer. You also need to have a non-swapable buffer in place right before the swapable one to account for the wildly different input impedances that might follow. In other words; You're forced to make a design that doesn't really do anything, no matter what op-amp you put in it.
I imagine the engineer at Fosi snickering a bit and going: "Here's something for the kids. Go nuts!"
True. But you can do measurements of the setup in question and look at the results in the lights of what we know with great certainty about human hearing.
Most likely the chances of the op-amp doing anything audible will be slim to say the least. Judgement will be perfectly in order.
Yes. But only way above the hard limits of biology. Below those, we are all screwed.
You can. With ABX or blind testing
Edit: https://www.audiosciencereview.com/...nefit-japanese-traditional-instruments.43632/
Killingbeans
Major Contributor
No. But we can get close enough statistically to make the absolute of "knowing" completely pointless.
No, You can't, because You still don't objectively know, if that, what they seem to "hear" is physically "true" or not, because of the subjective nature of one's hearing.
This You can't extrapolate...
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You could fMRI.
You and I may experience chocolate or vanilla ice cream differently. But we can use statistics to verify that what we experience with our senses as different between those two flavors is reproducible and consistent. If you eat something really sweet, then the comparison to something else will feel less sweet - so there is some test to test variability.
Along those same lines, subjective differences can be measured using science to step away from anything goes.
Killingbeans
Major Contributor
Not relevant.
Most self-proclaimed audiophiles like to think of themselves as mutant anomalies with hearing capabilities way beyond normal, and while you actually can substantially improve your abilities through training (actual training, not "critical listening"), the biological limitations are more or less equally cruel to all of us.
Yes, there's probably a few "mutants" out there with somewhat heightened hearing capabilities, but they are far, far between. The likelihood of any of the people, claiming to hear differences when no such can be found through measurements, being one of these select few, is practically nil.
Not to mention that these "mutants" also would be limited by the physical aspects of biology. The chance of their hearing organs being altered to a degree that makes them even remotely comparable to electronic measuring instruments, is again practically nil. They would look unattractive to a potential partner, and evolution would deem their mutation redundant. Their rarity would be mind-bogglingly high, and their existence would be short-lived.
The amount of people in this hobby claiming to have superhuman hearing is absolutely astronomical compared to a reasonable estimate of how many could actually exist.
Responding to these claims, by saying that the claim makers are either full of sh¤t or deluding themselves, is not rude. It's just the most sensible thing to do.
This gave me a nosebleed
The blind test is designed specifically to discard all the things in a subjective experience that can lead you away from an objective result.
Do you also believe that randomized clinical trials won't tell you how effective a medicin is when placebo is taken out of the equation?
Exactly what I did with a little Aiyima, which allowed OPamp rolling on both its I/V and LPF functions. I tested several combinations, running 44 measurements per channel each time (THD, THD+N, IMD, bandwidth, phase, jitter, SNR, linearity, crosstalk, etc…). A Motu Ultralite Mk5 was used as the capturing device to perform measurements with REW.
A friend of mine did the same exercice using an old Yamaha CDX-390 CD player and using a Focusrite for measurements.
Here below are some results (with the Aiyima only), restricted to few measurements showing tangible differences (bandwidth and phase were always the same for instance). Note the relatively low resolution of the device anyways and fact I used 16bits/44.1kHz dithered test files as we initially wanted to test CD players only.
I’m currently repeating the same kind of tests with a DAC of much higher resolution than the Aiyima. Conclusions shared below are the same, that said.
A * next the the OPamp indicates the original one in its original slot.
In addition, we also organized ABX tests, including random people as well as audiophiles. We used two tracks of our choice (including the famous Tracy Chapman - Fast Track) and accepted any track from our audiophiles friends. We recorded the output of the DAC with high resolution audio interface, and gave the anonymized files to our testers.
From the above, you can see that the LPF slot is a little more demanding to our OPamps. But it could be some socket issue too, and that is not to disregard. As @AnalogSteph suggested, running the test again for those in red and orange categories would be necessary (TBD).
All that said, only one of our audiophiles was able to spot the worst case scenario (here 0.4% THD) using a recording of his choice: it was a 24bits/192kHz file of the "Symphony No. 3 Op.55 Eroica IV. Finale“ and therefore slightly deviating from our initial idea to limit our tests to 16bits/44.1kHz.
I failed replicating his performance though (I tried hard). We then continued to include his file in the ongoing tests.
Conclusions have already been shared in this thread, nothing new under the sun. Don’t mess with the original design, avoid randomly swapping OPamps and don’t forget you might add connectors issues when doing so.
————
Flo
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Oops and I forgot to mention that I assumed discrete OPamp would perform worse. Some are good looking (isn’t it enough to believe they are better?) and it was fun to test too:
The AkLIAM LC2 was particularly unhappy in the LPF slot. It was the only one to create additional jitter. I supposed it was ringing all over the place, poor thing (yes, 12.5% THD ). No issue though when used as an I/V converter as you can see below:
————
Flo
The AkLIAM LC2 was particularly unhappy in the LPF slot. It was the only one to create additional jitter. I supposed it was ringing all over the place, poor thing (yes, 12.5% THD
). No issue though when used as an I/V converter as you can see below:————
Flo
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To throw in something here that might muddle the discussion, consider "blind sight" research in neuroscience. There are people who, due to specific damage to the visual cortex, have areas of vision on which they cannot consciously report. Yet they are able to respond to stimuli in those areas. So if you're talking to them about what the see in these visual areas, their report is uniformly "nothing." Yet their behavior shows that they nonetheless at some other level are aware of what's before their eyes in these blind areas.
The potential complication for A/B tests in audio is that, just as there can be nonreportable differences in what we see even though our behavior demonstrates that somehow unconsciously we're still seeing, and acting accordingly, there may possibly be nonreportable difference in what we hear, which in A/B tests we cannot report, but which nonetheless have significant effects on our behavior -- where in this case behavior includes level of enjoyment of music. Given the far-from-complete theories about why music even works, that some of the work may be significantly by communication across unconscious channels can't be safely discounted.
The feeling we get from music may be affected by nonreportable channels of musical perception, a "blind" sort of perception that won't show up in "blind" A/B tests. For my part, I've noticed that as I mix and match individual speakers as well as amplifiers, that new speakers or new amplifiers on several channels of a multi-channel AV setup will sound fine to me in the overall context, at first. But within a couple of weeks I develop a clear feeling of a mismatch, where the older, lesser speaker or amp no longer fits so well. What immediate conscious impression didn't reveal, awareness of seems to percolate up to the conscious level given more time.
I like A/B tests. The concept is clear. When they do show a difference, that's something quite real. But not showing an A/B difference may be less conclusive, just if there are unconscious levels of hearing just as there are of seeing.
The potential complication for A/B tests in audio is that, just as there can be nonreportable differences in what we see even though our behavior demonstrates that somehow unconsciously we're still seeing, and acting accordingly, there may possibly be nonreportable difference in what we hear, which in A/B tests we cannot report, but which nonetheless have significant effects on our behavior -- where in this case behavior includes level of enjoyment of music. Given the far-from-complete theories about why music even works, that some of the work may be significantly by communication across unconscious channels can't be safely discounted.
The feeling we get from music may be affected by nonreportable channels of musical perception, a "blind" sort of perception that won't show up in "blind" A/B tests. For my part, I've noticed that as I mix and match individual speakers as well as amplifiers, that new speakers or new amplifiers on several channels of a multi-channel AV setup will sound fine to me in the overall context, at first. But within a couple of weeks I develop a clear feeling of a mismatch, where the older, lesser speaker or amp no longer fits so well. What immediate conscious impression didn't reveal, awareness of seems to percolate up to the conscious level given more time.
I like A/B tests. The concept is clear. When they do show a difference, that's something quite real. But not showing an A/B difference may be less conclusive, just if there are unconscious levels of hearing just as there are of seeing.
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Brilliant work!
Killingbeans
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The comparison would only make sense if people with no damage to their visual cortex also showed signs of reacting to visual stimuli that can't be consciously reported.
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The return of the mythical thing.
You can tell if they can hear a difference. Only by hearing a differnece can they consistently tell two devices apart when they don't know which is playing. If they can't hear a difference and are therefore guessing, they'll get the same results as a coin toss.
This is what blind testing is for, and how it works.
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